android-activity/examples/na-subclass-jni/src/lib.rs

use android_activity::{AndroidApp, InputStatus, MainEvent, PollEvent};
use log::Level;
use log::{info, trace};
use serde::{Deserialize, Serialize};
use std::time::Duration;

#[derive(Debug, Serialize, Deserialize)]
struct AppState {
    uri: String,
}

#[no_mangle]
fn android_main(app: AndroidApp) {
    android_logger::init_once(android_logger::Config::default().with_min_level(Level::Info));

    let mut quit = false;
    let mut redraw_pending = true;
    let mut render_state: Option<()> = Default::default();

    while !quit {
        app.poll_events(
            Some(Duration::from_millis(500)), /* timeout */
            |event| {
                match event {
                    PollEvent::Wake => {
                        trace!("Early wake up");
                    }
                    PollEvent::Timeout => {
                        trace!("Timed out");
                        // Real app would probably rely on vblank sync via graphics API...
                        redraw_pending = true;
                    }
                    PollEvent::Main(main_event) => {
                        info!("Main event: {:?}", main_event);
                        match main_event {
                            MainEvent::SaveState { saver, .. } => {
                                let state = serde_json::to_vec(&AppState {
                                    uri: format!("foo://bar"),
                                })
                                .unwrap();
                                saver.store(&state);
                            }
                            MainEvent::Pause => {}
                            MainEvent::Resume { loader, .. } => {
                                if let Some(state) = loader.load() {
                                    let state: AppState = serde_json::from_slice(&state).unwrap();
                                    info!("Resumed with saved state = {state:#?}");
                                }
                            }
                            MainEvent::InitWindow { .. } => {
                                render_state = Some(());
                                redraw_pending = true;
                            }
                            MainEvent::TerminateWindow { .. } => {
                                render_state = None;
                            }
                            MainEvent::WindowResized { .. } => {
                                redraw_pending = true;
                            }
                            MainEvent::RedrawNeeded { .. } => {
                                redraw_pending = true;
                            }
                            MainEvent::LowMemory => {}

                            MainEvent::Destroy => quit = true,
                            _ => { /* ... */ }
                        }
                    }
                    _ => {}
                }

                if redraw_pending {
                    info!("Checking input: START");
                    if let Some(_rs) = render_state {
                        redraw_pending = false;

                        // Handle input
                        app.input_events(|event| {
                            info!("Input Event: {event:?}");
                            InputStatus::Unhandled
                        });

                        // Render...
                    }
                    info!("Checking input: DONE");
                } else {
                    info!("No redraw pending");
                }
            },
        );
    }
}

#[allow(non_snake_case)]
#[no_mangle]
pub extern "C" fn Java_co_realfit_nasubclassjni_MainActivity_notifyOnNewIntent(
    _env: jni::JNIEnv,
    _class: jni::objects::JObject, // This is the JClass, not the instance,
    _activity: jni::objects::JObject,
) {
    info!("onNewIntent was called!");
}